1、AMSC N/A FSC 5960 MIL-PRF-1/1657E 30 September 2009 SUPERSEDING MIL-PRF-1/1657D 1 October 2003 PERFORMANCE SPECIFICATION SHEET ELECTRON TUBE, NEGATIVE GRID (MICROWAVE) TYPE 8727 This specification is approved for use by all Departments and Agencies of the Department of Defense. The requirements for
2、acquiring the electron tube described herein shall consist of this document and the latest issue of MIL-PRF-1. DESCRIPTION: Triode, pencil, ceramic-metal. See figure 1. Mounting position: Any. Weight: 0.3 ounce (8.5 grams) nominal. ABSOLUTE RATINGS: Class C amplifier Parameter: Unit: Ef V Eb V dc Ec
3、 V dc Ehk V Rk Ohms Rg Meg Ik mA dc Ic mA dc Pp W TE C Barometric pressure, reduced mmHg Maximum: Minimum: 6.9 5.7 250 - 0 -50 +50 -50 - - 0.25 - 25 - 6 - 2.5 - 225 - 8 - Test condition: 6.3 125 8/ - 50 - - - - - - _ GENERAL: Qualification - Not required. INCH-POUND Provided by IHSNot for ResaleNo r
4、eproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1657E 2 TABLE I. Testing and inspection. Method Limits Inspection MIL-STD-1311 Notes Conditions Symbol Min Max Unit Conformance inspection, part 1 Total grid current 1266 3/ Eb = 200 V dc; Ec = -2 V dc; Rg = 0.5 Meg; Rk = 0 I
5、c 0 -0.3 A dc Electrode current (1) (anode) 1256 - Ck = 1,000 F Ib 9 19 mA dc Electrode current (2) (anode) 1256 - Ec = -5 V dc;Rk = 0 Ib - 50 A dc Transconductance (1) 1306 - Ck = 1,000 F Sm 12,500 19,500 mhos Output power (1) 4250 4/ Eb = 250 V dc Po 1.7 - W Conformance inspection, part 2 Heater c
6、urrent 1301 - Ef = 6.3 V If 205 245 mA Heater-cathode leakage 1336 - Ehk = +60 V dcEhk = -60 V dc IhkIhk - +30 -30 A dc A dc Transconductance (2) 1306 5/ Ef = 5.7 V Sm Ef - 15 % Direct-interelectrode capacitance 1331 1/ Cgp Cgk Cpk 1.53.6 - 2.7 5.00 0.040 pF pF pF Electrode current (3) (anode) 1256
7、- Ec = -2.5 V dcRk = 0 Ib 100 - A dc Amplification factor 1316 - Ck = 1,000 F Mu 55 85 - Insulation of electrodes 1211 - E(g-all) = -100 V dcE(p-all) = -300 V dc R 100 - Meg Output power (2) 4250 4/ Ef = 5.7 V;Eb = 250 V dc; do not retune cavityPo Ef - 0.2 W Conformance inspection, part 3 Sweep freq
8、uency vibration 1031 2/ 18/Ebb = 125 V dc; R1 = 10,000 ohms;Rk = 50 ohms Ep - 150 mV ac See footnotes at end of table. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1657E 3 TABLE I. Testing and inspection - Continued. Method Limits Inspec
9、tion MIL-STD-1311 Notes Conditions Symbol Min Max Unit Conformance inspection, part 3 - Continued Variable-frequency vibration 1031 2/ 18/Ebb = 125 V dc; R1 = 10,000 ohms;Rk = 50 ohms Ep - 150 mV ac Shock 1041 16/ 18/ Hammer angle = 30; no voltages applied - - - - Vibration fatigue 1031 17/ 18/ 2.5
10、G; fixed frequency; F = 25 Hz (min), 60 Hz (max) - - - - Shock and vibration fatigue-test end points: - Sweep and variable- frequency vibration 1031 - Ep - 200 mV ac Heater-cathode leakage 1336 - Ihk - 60 A dc Seal fracture - 6/ 7/ 18/ - 30 - pounds Seal strain - 7/ 18/ 19/ - - - - Heater-cycling li
11、fe1506 9/ 12/ 14/ Group D;Ef = 6.3 V; Ehk = 0;Eb = 0; Rk = 0; Ec = 0 - - - - Heater-cycling life-test end points: - Heater-cathodeleakage 1336 - Ehk = +60 V dcEhk = -60 v dc IhkIhk - +30 -30 A dc A dc Insulation of electrodes 1211 - E(g-all) = -100 V dc R 50 - Meg Stability life test (2 hours) 1516
12、11/ 12/ Group D;Eb = 215 V dc; Rk = 150 ohms; TA = room temp, 25C 5C; g1 grounded - - - - See footnotes at end of table. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1657E 4 TABLE I. Testing and inspection - Continued. Method Limits Insp
13、ection MIL-STD-1311 Notes Conditions Symbol Min Max Unit Conformance inspection, part 3 - Continued Stability life-test end point: - Transconductance (1) 1306 - Sm t - 15 % Survival-rate life 1521 13/ 15/ Stability life test,or equivalent conditions; TA = room temp, 25C 5C; t = 100 hours - - - - Sur
14、vival-rate life test end points: - Electrode current (2) (anode) 1256 - Ib - 50 A dc Transconductance (1) 1306 - Sm 9,000 - mhos Intermittent life 1501 10/ 14/ Group C;Ef = 6.3 V; Ebb = 250 V dc t 2,000 - cycles Intermittent life-test end points: - Output power (1) 4250 - Po 0.90 - W Total grid curr
15、ent 1266 - Ic - -1.0 A dc Insulation of electrodes 1211 - R 60 - Meg Barometric pressure, reduced 1002 18/ Pressure = 8 2 mmHg; voltage = 300 V ac - - - - 1/ Test in capacitance jig RCA Capacity Adapter Model H-1756E, or equivalent. A capacitance bridge operating frequency of 1.0 to 2.0 kHz may be u
16、sed. 2/ The tube shall be vibrated perpendicular to the major tube axis through a frequency range from 5 to 500 Hz and back. From 5 to 50 Hz, the tube shall be vibrated at a constant displacement of 0.040 0.0025 inch (1.02 0.06 mm). From 50 to 500 Hz, the tube shall be vibrated at a constant acceler
17、ation of 10 2 G. Total time to complete a sweep cycle shall be 10 5 minutes. a. Each tube shall be vibrated for 60 seconds at the frequency that gives maximum vibration output. If at the end of 60 seconds the vibration output is still increasing, the vibration shall continue until there is not furth
18、er increase. b. The tube shall be rejected for vibration output voltage exceeding the limit specified herein. 3/ This test is to be the first test performed at the conclusion of the holding period. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-
19、PRF-1/1657E 5 TABLE I. Testing and inspection - Continued. 4/ This test shall be performed in amplifier cavity Amerac Model No. 1244-1, or equivalent. Test frequency shall be 550 10 MHz. Input = 0.2 W. When the amplifier has been tuned, adjust Ec for Ib = 20 mA dc. 5/ Transconductance (2) is the per
20、cent change in transconductance (1) of an individual tube resulting from a change in Ef. 6/ Tube supported at cathode and anode terminals with the grid disk centered. The supports shall be placed 0.938 0.016 inch (23.83 0.41 mm) apart. Apply force to the grid disk without shock, perpendicular to the
21、 axis of the tube. Inspect for defects described in MIL-PRF-1, appendix D, Vacuum Seal (metal-to-glass) defect classification. 7/ Electrical rejects may be used. 8/ Whenever Ec is not specified on any test, the grid shall be grounded directly or through a grid resistor (if specified) except when rel
22、ated MIL-STD-1311 test methods imply grid variance to accomplish this test. 9/ The no-load to a steady-state full load of the heater voltage supply shall be not more than 3 percent. A failure or defect shall consist of an open heater, open cathode circuit, heater cathode short, or heater cathode lea
23、kage in excess of the specified heater cycling life-test end-point limit. 10/ Test shall be performed in amplifier cavity Amerac Model No. 1244-1, or equivalent. Test frequency shall be 550 10 MHz. Adjust Rk for Ik = 25 mA dc and Rg for Ig = 6 mA dc. 11/ Cycle Ef only, 110 minutes “on”, 10 minutes “
24、off”. 12/ Test shall be performed on a group D basis every 90 days with the lot consisting of the current month and two subsequent months. Failure of any tube shall revert back to group D monthly lot sampling. After three consecutive successful lot submissions have been completed, the test may rever
25、t to the quarterly basis. 13/ Test shall be performed in accordance with method 1521 and MIL-PRF-1 every 90 days. Failure of any tube shall revert back to MIL-PRF-1 monthly lot sampling. After three consecutive successful submissions have been completed, the test shall revert to the quarterly basis.
26、 14/ A complete cycle is made in a 6-minute period as follows: 3 minutes on, 3 minutes off. This is a destructive test. Mechanical or electrical rejects may be used. 15/ Tubes meeting the initial test requirements after stability and survival-rate life tests shall be accepted under this specificatio
27、n. 16/ Subject tubes to shock in axes X, Y, and Z for a total of 15 blows, five blows in each axis. 17/ Vibrate in axes X and Y only for a total of 64 hours, 32 hours in each axis. 18/ This specification sheet uses accept on zero defect sampling in accordance with MIL-PRF-1, table III. 19/ Use basic
28、 test method 2126 (for receiving tubes) for seal strain test of this ceramic tube type. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1657E 6 FIGURE 1. Outline drawing of electron tube type 8727.Provided by IHSNot for ResaleNo reproductio
29、n or networking permitted without license from IHS-,-,-MIL-PRF-1/1657E 7 Dimensions Ltr Inches Millimeters Notes Min Max Min Max Conformance inspection, part 1 C .555 .605 14.10 15.36 G .535 .575 13.59 14.60 H .320 - 8.13 - Y .650 .700 16.51 17.78 Conformance inspection, part 2 A - .230 - 5.84 B - .
30、180 - 4.57 D .165 .205 4.19 5.20 E .049 .055 1.24 1.40 F .120 .150 3.05 3.81 J .245 .252 6.22 6.40 2, 4 K - .115 - 2.92 L .335 .355 8.51 9.01 M .048 .068 1.22 1.73 N .547 .557 13.89 14.15 3 Q - .010 - 0.25 R .095 .125 2.41 3.17 S - 1.360 - 34.54 U .095 .135 2.41 3.43 V .020 .030 0.51 0.76 W .110 .12
31、0 2.79 3.05 X - .065 - 1.65 5 Reference dimensions AA .015 RAD 0.38 RAD AB .030 RAD 0.76 RAD AC .060 1.52 NOTES: 1. Reference plane “A” is defined as that plane against which annular surface “B” of the grid flange abuts. 2. The axis of the anode terminal shall be coincident with the axis of the cath
32、ode terminal within 0.010 inch (0.25 mm). 3. The axis of the cathode terminal shall pass through the exact center of the grid flange (dimension N) within 0.005 inch (0.13 mm). 4. With annular surface “B” resting on reference plane “A”, the axis of the cathode terminal (dimensions H and J) shall be w
33、ithin 2 degrees of a line perpendicular to reference plane “A”. 5. Leads shall be tinned except as specified by dimension X. Untinned length of leads shall be measured from end of ceramic stem wafer. FIGURE 1. Outline drawing of electron tube type 8727 - Continued. Provided by IHSNot for ResaleNo re
34、production or networking permitted without license from IHS-,-,-MIL-PRF-1/1657E 8 Referenced documents. In addition to MIL-PRF-1, this document references the following: MIL-STD-1311 The margins of this specification are marked with vertical lines to indicate where changes from the previous issue we
35、re made. This was done as a convenience only and the Government assumes no liability whatsoever for any inaccuracies in these notations. Bidders and contractors are cautioned to evaluate the requirements of this document based on the entire content irrespective of the marginal notations and relation
36、ship to the last previous issue. Custodians: Preparing activity: Navy - EC DLA - CC DLA - CC Review activities: (Project 5960-2009-033) Navy - AS, CG, MC, OS NOTE: The activities listed above were interested in this document as of the date of this document. Since organizations and responsibilities can change, you should verify the currency of the information above using the ASSIST Online database at http:/assist.daps.dla.mil/. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
